AP3984

Document number: DS37655 Rev. 3 - 2

3 of 15

www.diodes.com

December 2016

© Diodes Incorporated

AP3984

Pin Descriptions

Pin Number

Pin Name

Function

1

FB

The voltage feedback from auxiliary winding

2

CBC

This pin connects a resistor to GND for output cable compensation

3

VCC

This pin receives rectified voltage from the auxiliary winding of the transformer

4

CS

Current sense for primary side of transformer

5, 6

C

This pin is connected with an internal power BJT

’s collector

7

GND

This pin is the signal reference ground

Functional Block Diagram

Regulator

&

Bias

&

Latch

PFM

UVLO

UVLO

PFM

Valley

ON

R

Q

S

R

Q

S

FB

CBC

VCC

Cable

Compensation

Constant Voltage

Control

Constant Current

Control

Detector

0.1V

3

2

1

COMP

EA

Peak Current

Control & LEB

Dynamic

Response

Pro

Dyn

DAC

Shutdown

Line

Compensation

CS

No Load

Detection

NL

Dmin

NL

Auto-recovery

LVCC

DAC

COMP

VDD

Dyn

Enable

0.1V

Driver

OTP

Hold

SCP

VCC OVP

Transformer Saturation

Protection

FB_OVP/OCkP

Pro

Transformer Saturation

Protection

Transformer Saturation

Protection

GND

7

4

5,6

C